public interface Scheduler

• Method Summary

  All Methods

  Modifier and Type	Method and Description
  void	disconnected (SchedulerDriver driver) Invoked when the scheduler becomes "disconnected" from the master (e.g., the master fails and another is taking over).
  void	error (SchedulerDriver driver, java.lang.String message) Invoked when there is an unrecoverable error in the scheduler or driver.
  void	executorLost (SchedulerDriver driver, Protos.ExecutorID executorId, Protos.SlaveID slaveId, int status) Invoked when an executor has exited/terminated.
  void	frameworkMessage (SchedulerDriver driver, Protos.ExecutorID executorId, Protos.SlaveID slaveId, byte[] data) Invoked when an executor sends a message.
  void	offerRescinded (SchedulerDriver driver, Protos.OfferID offerId) Invoked when an offer is no longer valid (e.g., the slave was lost or another framework used resources in the offer).
  void	registered (SchedulerDriver driver, Protos.FrameworkID frameworkId, Protos.MasterInfo masterInfo) Invoked when the scheduler successfully registers with a Mesos master.
  void	reregistered (SchedulerDriver driver, Protos.MasterInfo masterInfo) Invoked when the scheduler reregisters with a newly elected Mesos master.
  void	resourceOffers (SchedulerDriver driver, java.util.List<Protos.Offer> offers) Invoked when resources have been offered to this framework.
  void	slaveLost (SchedulerDriver driver, Protos.SlaveID slaveId) Invoked when a slave has been determined unreachable (e.g., machine failure, network partition).
  void	statusUpdate (SchedulerDriver driver, Protos.TaskStatus status) Invoked when the status of a task has changed (e.g., a slave is lost and so the task is lost, a task finishes and an executor sends a status update saying so, etc).

• Method Detail

  • registered

    void registered(SchedulerDriver driver,
     Protos.FrameworkID frameworkId,
     Protos.MasterInfo masterInfo)

    Invoked when the scheduler successfully registers with a Mesos master. A unique ID (generated by the master) used for distinguishing this framework from others and MasterInfo with the IP and port of the current master are provided as arguments.

    Parameters:

    driver - The scheduler driver that was registered.

    frameworkId - The framework ID generated by the master.

    masterInfo - Info about the current master, including IP and port.

    See Also:

    SchedulerDriver, Protos.FrameworkID, Protos.MasterInfo

  • reregistered

    void reregistered(SchedulerDriver driver,
     Protos.MasterInfo masterInfo)

    Invoked when the scheduler reregisters with a newly elected Mesos master. This is only called when the scheduler has previously been registered. MasterInfo containing the updated information about the elected master is provided as an argument.

    Parameters:

    driver - The driver that was reregistered.

    masterInfo - The updated information about the elected master.

    See Also:

    SchedulerDriver, Protos.MasterInfo

  • resourceOffers

    void resourceOffers(SchedulerDriver driver,
     java.util.List<Protos.Offer> offers)

    Invoked when resources have been offered to this framework. A single offer will only contain resources from a single slave. Resources associated with an offer will not be re-offered to _this_ framework until either (a) this framework has rejected those resources (see SchedulerDriver.launchTasks(java.util.Collection<org.apache.mesos.Protos.OfferID>, java.util.Collection<org.apache.mesos.Protos.TaskInfo>, org.apache.mesos.Protos.Filters)) or (b) those resources have been rescinded (see offerRescinded(org.apache.mesos.SchedulerDriver, org.apache.mesos.Protos.OfferID)). Note that resources may be concurrently offered to more than one framework at a time (depending on the allocator being used). In that case, the first framework to launch tasks using those resources will be able to use them while the other frameworks will have those resources rescinded (or if a framework has already launched tasks with those resources then those tasks will fail with a TASK_LOST status and a message saying as much).

    Parameters:

    driver - The driver that was used to run this scheduler.

    offers - The resources offered to this framework.

    See Also:

    SchedulerDriver, Protos.Offer

  • offerRescinded

    void offerRescinded(SchedulerDriver driver,
     Protos.OfferID offerId)

    Invoked when an offer is no longer valid (e.g., the slave was lost or another framework used resources in the offer). If for whatever reason an offer is never rescinded (e.g., dropped message, failing over framework, etc.), a framework that attempts to launch tasks using an invalid offer will receive TASK_LOST status updates for those tasks (see resourceOffers(org.apache.mesos.SchedulerDriver, java.util.List<org.apache.mesos.Protos.Offer>)).

    Parameters:

    driver - The driver that was used to run this scheduler.

    offerId - The ID of the offer that was rescinded.

    See Also:

    SchedulerDriver, Protos.OfferID

  • statusUpdate

    void statusUpdate(SchedulerDriver driver,
     Protos.TaskStatus status)

    Invoked when the status of a task has changed (e.g., a slave is lost and so the task is lost, a task finishes and an executor sends a status update saying so, etc). If implicit acknowledgements are being used, then returning from this callback _acknowledges_ receipt of this status update! If for whatever reason the scheduler aborts during this callback (or the process exits) another status update will be delivered (note, however, that this is currently not true if the slave sending the status update is lost/fails during that time). If explicit acknowledgements are in use, the scheduler must acknowledge this status on the driver.

    Parameters:

    driver - The driver that was used to run this scheduler.

    status - The status update, which includes the task ID and status.

    See Also:

    SchedulerDriver, Protos.TaskStatus

  • frameworkMessage

    void frameworkMessage(SchedulerDriver driver,
     Protos.ExecutorID executorId,
     Protos.SlaveID slaveId,
     byte[] data)

    Invoked when an executor sends a message. These messages are best effort; do not expect a framework message to be retransmitted in any reliable fashion.

    Parameters:

    driver - The driver that received the message.

    executorId - The ID of the executor that sent the message.

    slaveId - The ID of the slave that launched the executor.

    data - The message payload.

    See Also:

    SchedulerDriver, Protos.ExecutorID, Protos.SlaveID

  • disconnected

    void disconnected(SchedulerDriver driver)

    Invoked when the scheduler becomes "disconnected" from the master (e.g., the master fails and another is taking over).

    Parameters:

    driver - The driver that was used to run this scheduler.

    See Also:

    SchedulerDriver

  • slaveLost

    void slaveLost(SchedulerDriver driver,
     Protos.SlaveID slaveId)

    Invoked when a slave has been determined unreachable (e.g., machine failure, network partition). Most frameworks will need to reschedule any tasks launched on this slave on a new slave. NOTE: This callback is not reliably delivered. If a host or network failure causes messages between the master and the scheduler to be dropped, this callback may not be invoked.

    Parameters:

    driver - The driver that was used to run this scheduler.

    slaveId - The ID of the slave that was lost.

    See Also:

    SchedulerDriver, Protos.SlaveID

  • executorLost

    void executorLost(SchedulerDriver driver,
     Protos.ExecutorID executorId,
     Protos.SlaveID slaveId,
     int status)

    Invoked when an executor has exited/terminated. Note that any tasks running will have TASK_LOST status updates automagically generated. NOTE: This callback is not reliably delivered. If a host or network failure causes messages between the master and the scheduler to be dropped, this callback may not be invoked.

    Parameters:

    driver - The driver that was used to run this scheduler.

    executorId - The ID of the executor that was lost.

    slaveId - The ID of the slave that launched the executor.

    status - The exit status of the executor.

    See Also:

    SchedulerDriver, Protos.ExecutorID, Protos.SlaveID, Protos.Status

  • error

    void error(SchedulerDriver driver,
     java.lang.String message)

    Invoked when there is an unrecoverable error in the scheduler or driver. The driver will be aborted BEFORE invoking this callback.

    Parameters:

    driver - The driver that was used to run this scheduler.

    message - The error message.

    See Also:

    SchedulerDriver